Means for rotating mixer bowls



May 15, 1951 Filed May 19, 1948 l. .qspsoN ums FOR aommcumza BOWLS I57,! I i/ZV/ z sheets-sum 1 I. JEPSON Isms FOR Ro'm'm IIXER Bowls 2sheetwshoe i 2 IN V EN TOR.

. ATTYS.

Patented May 15, 1951 MEANS FOR ROTATING MIXER BOWLS Ivar Jepson, OakPark, Ill., assignor to Sunbeam Corporation, Chicago, 111., acorporation of 1111- nois Application May 19, 1948, Serial No. 28,019,

9 Claims.

This invention relates to food mixers and more particularly to animproved drive means for positively eil'ecting the rotation of a mixingbowl.

It has long been a problem, in power driven food mixers, of providingsimple, inexpensive,

and satisfactory means for rotating the mixing bowl while the mixer isin operation to assure a thorough intermixing of the ingredients in themixing bowl. Heretofore the bowl has been rotated by the operator or theheaters have been arranged to turn the bowl through the medium of theingredients being mixed. However, in the latter case when theingredients vary in consistency there will be variation in the manner inwhich the mixing bowl is rotated. This is not entirely satisfactorysince the operator finds many instances in which he would like to beassured of predetermined rotation even when the consistency of themixture is that of a liquid. To overcome these objections, in oneinstance a driving head has been attached to a beater shaft to engagethe bowl and drive the latter while the heaters are rotating. While thisis an improvement over the previous constructions in which no directdriving means were employed, it has several disadvantages. This head hasbeen formed of metal. As a result it is found that a dark streak appearsin the bottom of the bowl where the metal engages the bowl. This isbelieved to be due to the small metal particles being abraded by thesurface of the glass mixing bowl. Metal driving heads also have thedisadvantage that they are relatively noisy in operation. Also, themetal tends to corrode when subjected to certain foods.

An object of this invention is, therefore, to provide a drive meansbetween a heater and the mixing bowl which has relatively long life,which is simple in construction and relatively inexpensive tomanufacture, and which will satisfactorily perform the desired bowlrotating function,

Another object of the invention is to provide a drive means of the abovecharacter which is not noisy in operation, which does not leave darkstreaks on the bottom of the bowl at the point of engagement with thebowl, and which is not efiected appreciably by foods with which it comesin contact.

Another object of the invention is to provide a drive means of the abovecharacter which is formed from material having sufiicient resiliency todistribute the pressure between the beater and the bowl over arelatively large contact area.

Another object of the invention is to provide 2 a novel means forsecuring the drive means to the beater.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which Figure 1 is an end viewof a food mixerand a cutaway view of a mixing bowl embodying the present invention;

Fig. 2 is a fragmentary sectional view taken substantially along theline 2-2 of Figure 1;v

Y Fig. 3 is an enlarged sectional view taken substantially along theline 3-3 of Figure 1;

Fig. 4 is a sectional view taken substantially along the line 44 of Fig.3;

Fig. 5 is a perspective view of a drive disc;

Fig. 6 is a further enlarged sectional view taken along the line 6-6 ofFig. 3;

Fig. '7 is a sectional view of a modified form of the invention;

Figs. 8 and 9 are sectional and bottom views, respectively, taken alongthe lines 88 and 9 9 of Fig. 7;

Fig. 10 is a sectional view of still another embodiment of theinvention;

Figs. 11 and 12 are sectional and bottom views, respectively, takensubstantially along the lines ||l l' and Ill-J2 of Fig. 10;

Fig. 13 is a sectional view of still another embodiment of theinvention; and

Figs. 14 and 15 are sectional and bottom views, respectively, takenalong the lines l4|4 and l5-l5 of Fig. 13.

Referring now to the drawings, the invention is shown embodied in anovel drive means for a food mixer in which a mixing bowl I lispositively rotated by one of the heaters l'2. As shown in Figure l forpurposes of illustration, the food mixer includes a base l3 having anupstanding support l4 mounted at one end of the base and a turntable I6shaped to support the mixing bowl H at the opposite end of the base. Amotor I! for driving the heaters I 2 and overlying the turntable ispivotally or otherwise suitably mounted on the support. To effect .thepivotal mounting in this instance the underside of the casing of themotor I I is formed with a lug l8 spaced from the casing and shaped tobe received between a hook shaped end H! of a lever 2| and a shoulder 22formed on the support I4, as shown in Figure 2. The lever is pivotallymounted on the support as by a pin 25 and is biased by a spring 23 tourge the hook shaped end into engagement with the lug [8. An adjustablestop 24 on the support I4 is provided for determining the at rest tweenone of the heaters l2 and the bowl H3;

As shown the disc 28 is formed with. anannular portion or edge 29 shapedto engage the bowl H. Preferably the disc is of such shape anddimenrsions that with the mixing. bowl position shown in Figure l theedge 29 engages the inclined side or bottom wall of the bowl. My inevention contemplates the provision of a disc formed of plastic materialhaving the qualities. namely, (a) good resistance to wear under therubbing, actionv involved. (-1)). relatively high co.- efficient offriction in contact with the bowl mate'- rial, (e) no: discolori-ng ormarking. of thebowl, (it) chemically inert withrespect to all foodsbeing mixed-,- to.) silent inv operation, f) inexpensive and easy tomanufacture, and (9') easy to: clean. -I have formed; this disc of apolyamide pl asfiic material preferably a poly-amide synthetic resinousmaterial known. asnylon. I have discovered. that with. such material thedisc 28. performs especially well: both with the bowl LLdry and. whenthere are ingredients init. This material. is. relatively unaffected byfoods .with. which it. comes in contact. The polyamide material hasespecially good wearing qualities and, doesnot abrade readily due, tothe action of the glass. onthe. driving disc 21L As a consequence thedriving disc does not leave a dark ring. or the like around the. edgesof the bowl H where the driving disc engages the latter. It;isbelieved:v that the relatively long life of. the driving. disc 2.8when. formed from polyamide material is due to the fact that thismaterial has. certain inherent resiliency.- IIhis permits the disc tochange its configuration. sufficiently to contorm at. least partially tothe curvature of the small cavities in the bowl surface. and. thusdistributes the pressure between the disc 28 and the bowl overarelatively large contact area. With this construction the, noise.resulting. from the frictional engagement. betweenv the bowl II and thedisc 28Lis of negligible, degree.

Suitable means is provided for positively retaining thedisc 2.8, inposition on. the. heater [2. For this. purpose as. shownv Figs. 2-5,the. disc is formed.- on one side. with-transversely extending grooves31. and. The latter are of thesame width as. the. bands. 33 and 34 whichcross, over, each. other and are secured to an elongated shait 3B1. asvby peening over the end of the shaft, tov fformthe heaters. l2, and aredis.- posjed on the disc 28 at angles corresponding to the anglesbetween thebands, 33 and 34; As shown in Figs. .4 and'.5 'the.bottoms ofthe grooves ;3'[.and 32 are of arcuate shape to fit the curvature ofthe'respective bands 33 and 34. As. best seen in Fig. 6. the groove 31. isformed with underside" walls 31 and 38. to form inwardly projectingportions 39 and 4|, respectively, shaped to overlie the band 33 andpositively secure the disc 28 to the beater l2". The resiliency of thepoly'amide material permits the disc 28 to be readily shapedintoposition on the end of the beater". It is to be understood thatwhere desired both grooves 3| and 32' may be'forme'd with 4 I inwardlyprojecting portions 39 and 4| shaped to engage the respective bands 33and 34. Also it is to be understood that the portions 39 and 4| of theside walls overlying the band 33 may be staked to insure against theaccidental removal of the driving disc 28 from the beater l2. A recess35 formed in the bottom of the groove 3| is provided for receiving; thepeened. over end of the. shafti3fi when thed'iscJis injposition. Discs28 of the above construction may be readily molded or formed by otherprocesses. The above disc. construction is also advantageous in that thedisc-may be readily removed and cleaned. Moreover, the disc is shapedand positioned so that it does. not. interfere with the cleaning of thebeater l2 on which it is mounted.

In.th e present instance, during operation of the mixer the drive disc28 is held in positive frictional' driving engagement with the bowl IIby the motor 11. For this purpose the stop 24 is adjusted. so that withthe heaters t2 in. the position. shown in- Figure 1 the motor is raisedabove the stop asv shown in Fig. 2. With the respective parts of. themixer in this positiontheweight of the motor I! positively urges thedrive disc- 28 into frictional engagement with the mixing bowl I l-..Rotation of the disc causes. the annular edge 29,- to engage the sideor. bottom. wall of. the bowl and in turn rotate the bowl. It is to beunderstood thatthe speed of rotationof thebowl necessarily depends onthe: speed. of the heaters. Thus if the boaters are; operating ata high.speed the bowl rotates faster than when the heaters are. operating. at alower speed.

' In the embodiment .of, the. invention shown in Figs. 7-9 the drivemember 42 of: material similar to the disc 28 is shown as beingmoldeddirect- 13 onthe lower end oi. a beater 49.. The portion of thedrive member extendingoutwardly from the beater is formed with anannularedge 4.:3 shaped to engage? the. bowl H, as in the manner described forthe embodiment shown in-.Figs ..1-6". The sleeve portion 44 of themolded driving member embraces a shaft46 and is connected at annularh,spaced points- 4-'! between cross bands 48 and. 4-9, with the driving;disc 42.

In the embodiment shown in Figs. 10-12 the drive disc 5| of materialsimilar to the disc 28 is rivetedit'o a. shaft 52. For this purpose. thedisc 5i is formed with a central. opening 53 shaped. to fit over thelower end" of the shaft 52:. To assemb le the disc 5| and; cross pieces54 and 55 on. the shaft 52', the: band 55' is positioned to abut againstashou lder 51 formed at the lower end of the shaft 52 and the band 56 isdisposed in side'by side relation with the band 54 and crosses over theband54,'as shown. A collar 58 is disposed on the extreme endof the shaftand is provided with a flange 59 shaped to engage a shoulder 5! formedin the countersunk portion 62 of the opening 53 in the disc 5|. The discis mounted on the collar 58 and the collar is positioned at the lowerend of the shaft 52. The extreme end of the shaft is of tubularconstruction and when the end 63 of the shaft is peened over against thecollar 58 as shown, the disc and the respective bands are clampedbetween the shoulder 57 and the peened over end 63.

In Figs. 13-15 there is shown still another embodiment of the invention.Herein a; disc $4 of a material similar to, the disc 28 is secured. to abeater 66 by a separate clamping means 61. The disc is formed with anannular shoulder 88 shaped to engage the mixing. bowl ,I I. The clamping5 means comprises an annular member (59 having an annular flange Hengageable with an annular shoulder 12 formed at the base of the disc58. The clamping means is also provided with four bendable arms 13, M,is and H. The arms are disposed so that with the disc 64 in the positionshown in Fig. 13 the respective arms are bent back on the side of thebands '58 and is away from the disc to positively secure the disc 64 tothe beater 66. As shown, the extreme ends of the arms are curved as atSt, 82, 83 and 84 so as to fit sungly up against the beater shaft 86.Where desired, these arms may be welded to the shaft after the assemblyof the disc on the beater.

While I have shown several embodiments of my invention it will beunderstood that I do not wish to be limited thereto since manymodifications may be made and I therefore contemplate by the claims tocover such modifications as fall within the true spirit and scope of myinvention.

I claim:

1. For use in a food mixer of the type comprising a rotatable mixingbowl and a rotatable power driven beater including a beater shaftadapted to be disposed in the mixing bowl, means for rotating saidmixing bowl in response to rotation of said beater comprising anon-metallic friction driving disc and means for fastening said disc tosaid beater adjacent the end of said beater shaft with the axes of saiddisc and shaft coaxial, whereby said disc is in frictional drivingengagement with the inside surface of the bottom of said bowl andgenerally immersed in the material mixed in said mixing bowl, theportion of said disc in frictional driving engagement with said bowlcomprising a relatively narrow annular portion, successive parts ofwhich drivingly engage with the inside surface of said bowl adjacent thejunction of the bottom and side wall thereof, said disc having goodresistance to wear under rubhing action with said bowl and having arelatively high coefficient of friction with said bowl, said disc beingrelatively chemically inert to substantially all materials mixed by saidfood mixer.

2. In a food mixer of the type in which a beater having radiallydisposed beater band members is utilized to rotate a mixing bowl, a discforming a frictional driving connection between said beater and thebowl, said disc having an annular edge on one side thereof engageablewith said bowl and having at least one transversely extending groove onits opposite side shaped to receive one of the band members of thebeater, the side walls of said groove being undercut to form spacedportions overhanging the band therein for securing the disc to thebeater, said overhanging portions being resilient to the extent topermit one of the band members to be received in the bottom of thegroove.

3. In a food mixer of the type in which a mixing bowl is rotated by abeater formed by band members secured to a shaft, a disc shaped to bedisposed between said beater and the bowl to form a frictional drivingconnection therebetween, said disc being formed from polyamide materialand having one side formed with an annular edge engageable with the bowland having its opposite side formed with grooves extending transverselyacross said disc and shaped to receive said band members, one of saidgrooves having spaced side walls overlying the bottom of the groove andshaped to overlie the band member therein to secure the disc to thebeater.

4. The combination set forth in claim 1, in which the beater hasradially disposed band members and the driving disc is provided with anannular shoulder in spaced relation to said annular portion, and anannular member having a flange engageable with said shoulder and havinga plurality of bendable arms capable of being deformed about the bandmembers of the beater to secure the disc to the beater.

5. The combination set forth in claim 1, in which the beater comprisesone or more bands and the annular portion of said driving disc comprisesan annular edge on one side engageable with said bowl and having anannular shoulder in spaced relation with said annular edge, and a ringmember shaped to engage said shoulder and having spaced arms adapted tobe bent over the bands forming the beater to secure the disc thereto.

6. The combination set forth in claim 1, in which the driving disc isformed from polyamide material molded on said beater.

7. A food mixer comprising a rotatable agitator having at least onebeater shaft, radially disposed bands attached to the lower end of saidshaft, a bowl freely revolubly mounted in juxtaposition to the agitatorso as to receive the agitator therein for mixing material in said bowl,a frictional member of nonenetallic material mounted on the lower end ofsaid beater shaft and projecting below the end of said heater shaft,said frictional member engaging in a torque transmitting manner saidradially disposed bands at a point beyond the circumference of saidheater shaft and in luding means for rigidly interrelating said shaft,said member and said radially disposed bands, said member having anannular portion engageabie with the inside surface of said bowl therebyautomatically revolving the bowl when the agitator is operated.

8. The combination set forth in claim 1, in

which said driving disc is a polyamide disc.

having a second surface portion capable of being in intimate engagementwith band members whereby a torque for rotating is transmitted theretothrough said members, and means for fastening said disc to said beaterwith said second surface portion in torque transmitting relationshipwith said band members.

IVAR JEPSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,008,184 Mross July 16, 19352,270,164 Du Rietz et al. Jan. 13, 1942

